In Situ FT-IR Spectroscopic Study of CO(2) and CO Adsorption on Y(2)O(3), ZrO(2), and Yttria-Stabilized ZrO(2).
In Situ FT-IR Spectroscopic Study of CO(2) and CO Adsorption on Y(2)O(3), ZrO(2), and Yttria-Stabilized ZrO(2).
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DOI：
10.1021/jp405625x
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发表时间：
2013-08-29
期刊：
影响因子：
--
通讯作者：
Penner S
中科院分区：
文献类型：
--
作者：
Köck EM;Kogler M;Bielz T;Klötzer B;Penner S
利用原位FT-IR光谱研究了CO2和CO在市售氧化钇稳定的ZrO 2（8摩尔% Y，YSZ-8），Y2 O3和ZrO 2上的吸附。所有这三种氧化物在高温（1173 K）在空气中进行预处理，这导致有效的脱羟基纯氧化锆。Y_2O_3和YSZ-8对CO和CO_2的吸附反应性都比ZrO_2高得多，这是因为含Y相更容易再羟基化。几种不同的碳酸盐物种已观察到CO2吸附Y2 O3和YSZ-8，这是更强烈地结合在前者，由于形成更高的协调多齿碳酸盐物种退火后。作为控制碳酸盐形成的关键因素，Y-中心上的活性（碱性）表面羟基的存在被确定。因此，CO2的化学吸附最有可能包括将CO2分子插入反应性表面羟基中，随后形成碳酸氢盐物质。甲酸盐形成CO吸附后，已观察到所有三种氧化物，但不太明显，由于在高温处理过程中的表面的有效脱羟基的氧化锆。后者通常会导致抑制ZrO 2样品的表面反应性，涉及CO或CO2作为反应中间体的反应。
In situ FT-IR spectroscopy was exploited to study the adsorption of CO2 and CO on commercially available yttria-stabilized ZrO2 (8 mol % Y, YSZ-8), Y2O3, and ZrO2. All three oxides were pretreated at high temperatures (1173 K) in air, which leads to effective dehydroxylation of pure ZrO2. Both Y2O3 and YSZ-8 show a much higher reactivity toward CO and CO2 adsorption than ZrO2 because of more facile rehydroxylation of Y-containing phases. Several different carbonate species have been observed following CO2 adsorption on Y2O3 and YSZ-8, which are much more strongly bound on the former, due to formation of higher-coordinated polydentate carbonate species upon annealing. As the crucial factor governing the formation of carbonates, the presence of reactive (basic) surface hydroxyl groups on Y-centers was identified. Therefore, chemisorption of CO2 most likely includes insertion of the CO2 molecule into a reactive surface hydroxyl group and the subsequent formation of a bicarbonate species. Formate formation following CO adsorption has been observed on all three oxides but is less pronounced on ZrO2 due to effective dehydroxylation of the surface during high-temperature treatment. The latter generally causes suppression of the surface reactivity of ZrO2 samples regarding reactions involving CO or CO2 as reaction intermediates.
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影响因子：
3.9
作者：
Bachiller-Baeza, B;Rodriguez-Ramos, I;Guerrero-Ruiz, A
通讯作者：
Guerrero-Ruiz, A
影响因子：
3.3
作者：
Collins, SE;Baltanás, MA;Bonivardi, AL
通讯作者：
Bonivardi, AL
影响因子：
3.9
作者：
Pokrovski, K;Jung, KT;Bell, AT
通讯作者：
Bell, AT
影响因子：
3.3
作者：
Calatayud, M.;Collins, S. E.;Bonivardi, A. L.
通讯作者：
Bonivardi, A. L.
影响因子：
6.2
作者：
Viazzi, Celine;Bonino, Jean-Pierre;Barnabe, Antoine
通讯作者：
Barnabe, Antoine